TIPS Block vs Dual Subsartorial Block

TIPS Block vs Dual Subsartorial Block for Total Knee Arthrolplasty: Double Blinded Randomized Controlled Study

The present study examine adding local anesthetic injection superior to the sartorius at the level of the femoral triangle to block the intermediate femoral cutaneous nerve (IFCN) which is responsible for innervation of the anterior thigh and the proximal part of the parapatellar incision used for TKA. This may provide superior analgesia when added to dual subsartorial blockade in cases of total knee arthroplasty

Introduction: Maximum pain control with regional analgesic techniques after total knee arthroplasty (TKA) is crucial for early rehabilitation after surgery. The ideal regional anesthetic technique should cover all the essential innervations of the knee joint involved in each surgical step without causing motor blockade. The investigators hypothesize that local anesthetic injection superior to the sartorius at the level of the femoral triangle may block the intermediate femoral cutaneous nerve (IFCN) which is responsible for innervation of the anterior thigh and the proximal part of the parapatellar incision used for TKA and provide superior analgesia when added to dual subsartorial blockade in cases of total knee arthroplasty. Patients will be divided into 2 groups. Group TIPS; patients will receive double level subsartorial block and suprasartorial LA injection at the level of the distal FT after induction of general anesthesia (GA). Group Dual; patients will receive double level subsartorial canal block after induction of GA. Upon arrival to the operating room (OR), a multichannel monitor will be attached to patients, followed by the administration of 2 mg midazolam IV after securing an IV cannula. Induction of anesthesia will be carried out with 2 mic/kg fentanyl, 2 mg/kg propofol and 25 mg atracurium followed by insertion of a proper size LMA. Patients will be randomly allocated into 2 groups by a computer generated program into 2 groups Group Dual: Patients will receive a combination of femoral triangle block and distal ACB. Femoral triangle block will be given just (1-2 cm) proximal to the apex of the femoral tringle which is the point at which the medial border of the sartorius muscle (STM) meets the medial border of the adductor longus muscle (ALM). Ten ml of 0.25 % bupivacaine mixed with 2 mg dexamethasone will be injected just below the STM. Another 20 ml of 0.25 % bupivacaine mixed with 2 mg dexamethasone will be injected in the lower one-third of the adductor canal. At this level, femoral vessels dip into the opening of the adductor hiatus to become popliteal vessels. Sonoanatomy of this region shows the adductor magnus muscle (AMM) posteromedially, vastus medialis muscle (VMM) anterolaterally, and the STM medially. Group TIPS: Patients will receive dual injection subsartorial block and a third injection of 10 ml of 0.25 % bupivacaine superficial to the sartorius under the facia lata. Postoperatively, multimodal analgesia regimen will be continued in the form of paracetamol 1 g /8 hours and ketorolac 30 mg /8 hours intravenously for 24 hours. Intravenous morphine patient controlled analgesia will be started after induction of GA at a concentration of 0.5 mg/ml with a background infusion rate of 70 mic/kg/hr and on demand dose of 1 mg with a lockout interval of 10 minutes. Resting and dynamic VAS assessment will be carried out every 4 hours during the 24 hour follow up period. Total postoperative morphine requirements will be measured during the postoperative follow up period. Postoperative functional outcome will be assessed using the Timed Up and Go (TUG) test and the 30-second Chair Stand Test (30s-CST).

patients will receive double level subsartorial block and suprasartorial LA injection at the level of the distal FT after induction of general anesthesia (GA)

Drug: Bupivacaine 0.25 % mixed with 2 mg dexamethasone. Patients will receive a combination of femoral triangle block and distal ACB. Femoral triangle block will be given just (1-2 cm) proximal to the apex of the femoral tringle which is the point at which the medial border of the sartorius muscle (STM) meets the medial border of the adductor longus muscle (ALM). Ten ml of 0.25 % bupivacaine mixed with 2 mg dexamethasone will be injected just below the STM. Another 20 ml of 0.25 % bupivacaine mixed with 2 mg dexamethasone will be injected in the lower one-third of the adductor canal. At this level, femoral vessels dip into the opening of the adductor hiatus to become popliteal vessels. Sonoanatomy of this region shows the adductor magnus muscle (AMM) posteromedially, vastus medialis muscle (VMM) anterolaterally, and the STM medially Patients will receive a third injection of 10 ml of 0.25 % bupivacaine superficial to the sartorius under the facia lata

Drug: Bupivacaine 0.25 % mixed with 2 mg dexamethasone Patients will receive a combination of femoral triangle block and distal ACB. Femoral triangle block will be given just (1-2 cm) proximal to the apex of the femoral tringle which is the point at which the medial border of the sartorius muscle (STM) meets the medial border of the adductor longus muscle (ALM). Ten ml of 0.25 % bupivacaine mixed with 2 mg dexamethasone will be injected just below the STM. Another 20 ml of 0.25 % bupivacaine mixed with 2 mg dexamethasone will be injected in the lower one-third of the adductor canal.

Postoperative resting visual analogue scale score.It's a 0-10 score where 0 is no pain and 10 is the worst pain

Resting visual analogue scale score assessment will be carried out every 4 hours during the 24 hour follow up period

Postoperative dynamic visual analogue scale score. It's a 0-10 score where 0 is no pain and 10 is the worst pain

Dynamic visual analogue scale score assessment will be carried out every 4 hours during the 24 hour follow up period

30-second Chair Stand Test (30s-CST). The number of times the patient can stand and sit in 30 seconds

Inclusion Criteria: American Society of Anesthesiologists (ASA) physical status I-III Scheduled for unilateral total knee arthroplasty Exclusion Criteria: BMI > 35 kg/m2 Pre-existing neurological deficit Any disability of the non-operated limb preventing fair mobilization Infection at the site of injection Chronic opioid users/abusers

The datasets used and analyzed during the current study are available from the corresponding author upon reasonable request

Ishiguro S, Yokochi A, Yoshioka K, Asano N, Deguchi A, Iwasaki Y, Sudo A, Maruyama K. Technical communication: anatomy and clinical implications of ultrasound-guided selective femoral nerve block. Anesth Analg. 2012 Dec;115(6):1467-70. doi: 10.1213/ANE.0b013e31826af956. Epub 2012 Aug 10.

Ludwigson JL, Tillmans SD, Galgon RE, Chambers TA, Heiner JP, Schroeder KM. A Comparison of Single Shot Adductor Canal Block Versus Femoral Nerve Catheter for Total Knee Arthroplasty. J Arthroplasty. 2015 Sep;30(9 Suppl):68-71. doi: 10.1016/j.arth.2015.03.044. Epub 2015 Jun 3.